Prosecutors in Michigan say that the parents of accused school shooter Ethan Crumbley ignored clear warning signs their teenage son was a possible danger to himself or others while they paid for attention to their horses — while one had an extramarital affair.

As previously reported, Ethan Crumbley, 15, is suspected of killing four students and injuring seven more after he opened fire at Oxford High School on November 30. The teen allegedly brought a gun to school that his father had bought him a few days prior. On the morning of the shooting, a teacher raised concern about a note and illustrations the student had made. Crumbley’s parents were called to the school but chose not to take their son home, and school administrators allowed him to return to class.

Crumbley was taken into custody without incident shortly after opening fire, and his parents were arrested on manslaughter charges days later after an apparent attempt to flee. In a response to their defense team’s request for modified bond obtained by 12 News, prosecutors argued that Crumbley’s parents James and Jennifer Crumbley are a flight risk and failed to intervene when their son allegedly demonstrated signs of potential violence.

“Defendants were in a better position than anyone else in the world to prevent this tragedy, but they failed to do so,” the filing reportedly states.

Prosecutors reportedly argued that Ethan Crumbley’s parents knew at the time of the shooting that their son was depressed, lacked meaningful social connections, and was “fascinated” with guns.

“The facts laid out in the brief we submitted to the court today speak for themselves,” Oakland County, Michigan, Chief Assistant Prosecutor David Williams said in a statement obtained by the news station. “And based on those facts, we strongly believe that the bond for James and Jennifer Crumbley [$500,000 each] was set appropriately.”

Prosecutors reportedly alleged that Ethan Crumbley had been sending his mother texts demonstrating a disturbed state of mind for months before the shooting. They also alleged that the teen had tortured animals and kept “baby bird’s head in a jar on his bedroom floor.”

“Instead of paying attention to their son and getting him help, they bought him a gun,” the filing states, according to the 12 News report.

The attorneys for the state argued in the filing that James and Jennifer Crumbley put their own recreational needs ahead of their son’s emotional needs, spending an excessive time caring for their horses. The prosecutors also alleged that the elder Crumbleys had substance abuse issues and that one had an extramarital affair. Further, prosecutors alleged the parents “attempted to destroy one of the” four cell phones they had at the time of their arrest in Michigan, where they appeared to have been hiding in a commercial building.

And the filing alleges the parents continued to put their own needs ahead of their son’s even after his arrest. Jennifer Crumbley reportedly wrote in a text to a co-worker that her son’s destiny is done and she has to take care of herself.”

Ethan Crumbley is being held on four counts of first-degree murder, one count of terrorism causing death, seven counts of assault with intent to murder and 12 counts of possession of a firearm during the commission of a felony. He will be tried as an adult.

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